Clinical features and prognosis of a sample of patients with trisomy 13 (Patau syndrome) from Brazil

Abstract

Trisomy 13 or Patau syndrome (PS) is a chromosomal disorder characterized by a well known presentation of multiple congenital anomalies. Our objective was to determine the clinical features and prognosis observed in a sample of patients with PS. The series was composed of patients with diagnosis of PS consecutively evaluated by a Clinical Genetics Service from a reference hospital of southern Brazil, in the period between 1975 and 2012. Statistical analysis was performed using PEPI program (version 4.0), with two-tailed Fisher's exact test for comparison of frequencies (P<0.05). The sample consisted of 30 patients, 60% male, median age at first evaluation of 9 days. Full trisomy of chromosome 13 was the main cytogenetic alteration (73%). The major clinical findings included: cryptorchidism (78%), abnormal auricles (77%), congenital heart defects (76%), polydactyly (63%), microphthalmia (60%) and micrognathia (50%). Four patients (13%) simultaneously had micro/anophthalmia, oral clefts and polydactyly. Some findings were only observed in our sample and included, among others, preauricular tags (10%), duplication of the hallux (3%) and spots following the lines of Blaschko (3%). Mosaicism (20% of cases) had a statistically significant association only with absence of cryptorchidism. The median of survival was 26 days. Patients with and without mosaicism had similar median of survival. Our findings, in agreement with the literature, show that the anomalies in patients with PS can be quite variable, sometimes even atypical. There is no pathognomonic finding, which may make the early identification of these patients challenging.

Trisomy 13 Presented with Bilateral Anophthalmia, Postaxial Polydactyly on the Left Foot and Coarse Facial Appearance in a Newborn Infant: Case Report

“…7 Other described ocular abnormalities in trisomy 13 include iris coloboma, persistent primary hyperplastic vitreous (PPHV), cataract, cyclopia, primary aphakia, bupthalmos due to congenital glaucoma. 4 Bilateral prominent anophthalmia including disorganized remnants of intraocular structures associated with trisomy 13 had been observed in our patient. To our knowledge, this is the unique case of trisomy 13 with bilateral anophthalmia accompanied by disorganized intraocular structures and postaxial polydactyly of right foot.…”

“…According to the results of 30 cases discussed in a review, the main findings were cryptorchidism (78%), abnormal auricles (77%), polydactyly of hands and/or feet (63%), microphtalmia (60%), micrognathia (50%), low-set ears (47%), aplasia cutis/scalp defects (43%) and microcephaly (40%). 4 In our patient we revealed that bilateral anophthalmia, postaxial polydactyly of foot, micrognathia, abnormal auricles, large nose, short neck, hypoplastic toe nails. Postaxial polydactyly in Patau syndrome is one of the key elements of diagnosis and reported in 52-70% of cases.…”

Nine children over the age of one year with full trisomy 13: A case series describing medical conditions

“…The absence of this brain anomaly may be an additional factor in long-term survival. Petry et al [2013] noted a high incidence of cardiac defects in 24 infants with trisomy 13 (additional six were mosaic). Close to 40% of infants in Pont et al [2006] were diagnosed with a condition such as ASD or VSD.…”

“…Baty et al [1994] also discussed that approximately one-third of their sample was living at the age of one year and 13% at the age of five. Other studies offer lower survival rates [e.g., Lin et al, 2007;Crider et al, 2008;Petry et al, 2013]. Mean age when TRIS Survey was completed was 35 months and most of the sample (78%) was still living several years later.…”

“…[Lin et al, 2007;Petry et al, 2013]. Many infants also present with cardiac anomalies including patent ductus arteriosus (PDA) or ventricular septal defect (VSD), respiratory difficulties including central apnea and upper airway problems and feeding difficulties [Rios et al, 2004;Pont et al, 2006;Hsu and Hou, 2007;Jones et al, 2013].…”